Abstract
Gene methylation MMR (mismatch repair) leads to the formation of tumors of the right colon often mucinous appearance. Microsatellite instability (MSI) is associated with resistance to 5-fluorouracil, however prognosis of hypermutated and MSI-high tumors is better than other subtypes.
Conversely, group of mucinous carcinomas with microsatellite stable (MSS) but with MGMT methylation (0-6 methylene thylguanin DNA methyltransferase) has a poor prognosis. The last group are right-sided tumors with Ras mutations of genes (also called p21 ras), resistant to anti-EGFR therapy, which also have a poor prognosis.
Negative prognostic sign is a mutation of the BRAF gene. High frequency of mutational load (MSI-high, CIMP-high, BRAF) is associated in particular with the ascending colon and generally with tumors of the right colon and transverse colon but with the exception of caecum.
The author brings a case of a patient with mucinous adenocarcinoma who takes place at the targeted therapy cetuximab for 35 months.